Fuses and Relays

FUSES AND RELAY
FUSES: Fuses are electrical device that helps to cut off a circuit connection in case of excess amperage or voltage through the circuit that could damage the component or system.

Most electrical and electronic components or devices are usually fused in their circuit, every circuit has a maximum amount of amperage or voltage allowed to go through it, the fuse is used to control the amount of amperage from the power source to the device or components which is being powered.

When excess amount of current above the fuse limit the fuse is blown out and damaged, a bad or damaged can be physically observed as the conductor in a damaged is usually open circuit. When the fuse is bad the circuit is opened, therefore causing power to be shut off from the component or system.

The fuses in the vehicle are usually located in the fuses box, the fuse box may also contain relays; the fuses are usually pulled out using special pliers. The amperage on the fuse can be tested using the multimeter; the fused usually have two terminals which the testing led of the multimeter can be placed on them in any order for the amperage test.

RELAY: Relay is a switching device that uses low current (amperage) circuit to power high current (amperage) circuit. It helps in controlling the supply of power to an electrical or electronics components or systems, just as the fuse a blown out or damaged relay would create an open circuit.
There are usually various types of relay depending on the device it is used to power it.